Field assessments of heart rate dynamics during spawning migration of wild and hatchery-reared Chinook salmon.

During spawning, adult Pacific salmonids (Oncorhynchus spp.) complete challenging upriver migrations during which energy and oxygen delivery must be partitioned into activities such as locomotion, maturation and spawning behaviours under the constraints of an individual's cardiac capacity. To advance our understanding of cardiac function in free-swimming fishes, we implanted migrating adult Chinook salmon (Oncorhynchus tshawytscha) collected near the mouth of the Sydenham River, Ontario, with heart rate (fH) biologgers that recorded fH every 3 min until these semelparous fish expired on spawning grounds several days later. Fundamental aspects of cardiac function were quantified, including resting, routine and maximum fH, as well as scope for fH (maximum-resting fH). Predictors of fH were explored using generalized least-squares regression, including water temperature, discharge, fish size and fish origin (wild versus hatchery). Heart rate was positively correlated with water temperature, which aligned closely with daily and seasonal shifts. Wild fish had slower resting heart rates than hatchery fish, which led to significantly higher scope for fH. Our findings suggest that wild salmon may have better cardiac capacity during migration than hatchery fish, potentially promoting migration success in wild fish. This article is part of the theme issue 'Measuring physiology in free-living animals (Part I)'.

Drivers of pro-environmental behaviours among outdoor recreationists: The case of a recreational fishery in Western Canada.

Pro-environmental behaviours (PEBs) are important for mitigation and restoration efforts in the Anthropocene. As recreationists are motivated to engage in leisure activities to increase their own personal wellbeing, we submit that threats to wellbeing (an egocentric motivator) predict engagement in PEBs amongst recreationists. We also predict that differences in experiences across groups of recreationists leads to differences in PEB engagement. Using an online survey, we test our two hypotheses (if recreationists perceive there is a threat to their wellbeing and that their behaviours can yield environmental successes, then they will be more likely to engage in PEBs, and if recreationists differ in recreational experiences then they will demonstrate differences in PEB engagement) amongst outdoor recreationists, specifically Canadian rainbow trout and steelhead anglers in British Columbia (n = 894 respondents). We define 'threat to wellbeing' as the interaction of environmental threat-perceptions of used environments for fishing, and level of centrality fishing has to one's lifestyle. To test our first hypothesis, we conducted three linear regressions corresponding to three different PEBs related to catch-and-release (C&R) fishing. Our egocentric predictor 'threat to wellbeing' was only significant for one out of the three PEBs tested, showing mixed support for our first hypothesis. It is of note that 'environmental threat perceptions' and one's belief in successes resulting from PEB engagement were found to be significant predictors for all three PEBs tested. These results suggest that predictors of PEB may not always be transferable across PEBs relating to recreational activities, and environmental threat perception and one's belief in successes resulting from PEB engagement are strong predictors of PEBs amongst recreationists. To test our second hypothesis, we conducted a Kruskal Wallis test to determine if there were significant differences across angler groups in PEB predictor scores and PEB engagement and conducted pairwise population Z-tests to determine proportional participation rates across angler groups for the three PEBs and PEB predictors investigated. Experiences were found to shape predictors of PEBs, as well as likelihood to engage in PEBs, as different angler groups targeting different fish (i.e., rainbow trout vs steelhead) and using different aquatic habitats (i.e., rivers vs. lakes) demonstrated significantly different scores for PEB predictors, as well as significantly different likelihood to engage in two of the three PEBs tested. These findings support the notion that recreationists are not a homogenous group, and that their beliefs and resulting behaviours during recreational activities are determined by their experiences in nature and can be influenced by the species with which they interact, and the habitats they use for recreation.

COVID-19 restrictions and recreational fisheries in Ontario, Canada: Preliminary insights from an online angler survey.

The COVID-19 pandemic and corresponding public health mitigation strategies have altered many facets of human life. And yet, little is known about how public health measures have impacted complex socio-ecological systems such as recreational fisheries. Using an online snowball survey, we targeted resident anglers in Ontario, Canada, to obtain preliminary insights on how the pandemic has impacted recreational fishing and related activity. We also explored angler perspectives on pandemic-related restrictions and other aspects of fisheries management. Our results point to the value of recreational fisheries for the mental and physical well-being of participants, as well as the value and popularity of outdoor recreation during a pandemic. Although angling effort and fish consumption appeared to decline during the early phases of the pandemic, approximately 21 % of the anglers who responded to our survey self-identified as new entrants who had begun or resumed fishing in that time. Self-reported motivations to fish during the pandemic suggest that free time, importance to mental and physical health, and desires for self-sufficiency caused some anglers to fish more, whereas a lack of free time, poor or uncertain accessibility, and perceived risks caused some anglers to fish less. Respondents also expressed their desires for more clear and consistent communication about COVID-19 fishing restrictions from governments, and viewed angling as a safe pandemic activity. Information on recreational angler behaviours, motivations, and perspectives during the pandemic may prove valuable to fisheries managers and policy makers looking to optimize their strategies for confronting this and other similar crises.